sunrpc/clnt_udp.c

   1 /* @(#)clnt_udp.c       2.2 88/08/01 4.0 RPCSRC */
   2 /*
   3  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   4  * unrestricted use provided that this legend is included on all tape
   5  * media and as a part of the software program in whole or part.  Users
   6  * may copy or modify Sun RPC without charge, but are not authorized
   7  * to license or distribute it to anyone else except as part of a product or
   8  * program developed by the user.
   9  *
  10  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  11  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  12  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  13  *
  14  * Sun RPC is provided with no support and without any obligation on the
  15  * part of Sun Microsystems, Inc. to assist in its use, correction,
  16  * modification or enhancement.
  17  *
  18  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  19  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  20  * OR ANY PART THEREOF.
  21  *
  22  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  23  * or profits or other special, indirect and consequential damages, even if
  24  * Sun has been advised of the possibility of such damages.
  25  *
  26  * Sun Microsystems, Inc.
  27  * 2550 Garcia Avenue
  28  * Mountain View, California  94043
  29  */
  30 #if !defined(lint) && defined(SCCSIDS)
  31 static char sccsid[] = "@(#)clnt_udp.c 1.39 87/08/11 Copyr 1984 Sun Micro";
  32 #endif
  33
  34 /*
  35  * clnt_udp.c, Implements a UDP/IP based, client side RPC.
  36  *
  37  * Copyright (C) 1984, Sun Microsystems, Inc.
  38  */
  39
  40 #include <stdio.h>
  41 #include <unistd.h>
  42 #include <libintl.h>
  43 #include <rpc/rpc.h>
  44 #include <rpc/xdr.h>
  45 #include <rpc/clnt.h>
  46 #include <sys/poll.h>
  47 #include <sys/socket.h>
  48 #include <sys/ioctl.h>
  49 #include <netdb.h>
  50 #include <errno.h>
  51 #include <rpc/pmap_clnt.h>
  52 #include <net/if.h>
  53 #include <ifaddrs.h>
  54 #ifdef USE_IN_LIBIO
  55 # include <wchar.h>
  56 #endif
  57
  58 #ifdef IP_RECVERR
  59 #include <errqueue.h>
  60 #include <sys/uio.h>
  61 #endif
  62
  63 extern bool_t xdr_opaque_auth (XDR *, struct opaque_auth *);
  64 extern u_long _create_xid (void);
  65
  66 /*
  67  * UDP bases client side rpc operations
  68  */
  69 static enum clnt_stat clntudp_call (CLIENT *, u_long, xdrproc_t, caddr_t,
  70                                     xdrproc_t, caddr_t, struct timeval);
  71 static void clntudp_abort (void);
  72 static void clntudp_geterr (CLIENT *, struct rpc_err *);
  73 static bool_t clntudp_freeres (CLIENT *, xdrproc_t, caddr_t);
  74 static bool_t clntudp_control (CLIENT *, int, char *);
  75 static void clntudp_destroy (CLIENT *);
  76
  77 static struct clnt_ops udp_ops =
  78 {
  79   clntudp_call,
  80   clntudp_abort,
  81   clntudp_geterr,
  82   clntudp_freeres,
  83   clntudp_destroy,
  84   clntudp_control
  85 };
  86
  87 /*
  88  * Private data kept per client handle
  89  */
  90 struct cu_data
  91   {
  92     int cu_sock;
  93     bool_t cu_closeit;
  94     struct sockaddr_in cu_raddr;
  95     int cu_rlen;
  96     struct timeval cu_wait;
  97     struct timeval cu_total;
  98     struct rpc_err cu_error;
  99     XDR cu_outxdrs;
 100     u_int cu_xdrpos;
 101     u_int cu_sendsz;
 102     char *cu_outbuf;
 103     u_int cu_recvsz;
 104     char cu_inbuf[1];
 105   };
 106
 107 /*
 108  * Create a UDP based client handle.
 109  * If *sockp<0, *sockp is set to a newly created UPD socket.
 110  * If raddr->sin_port is 0 a binder on the remote machine
 111  * is consulted for the correct port number.
 112  * NB: It is the clients responsibility to close *sockp.
 113  * NB: The rpch->cl_auth is initialized to null authentication.
 114  *     Caller may wish to set this something more useful.
 115  *
 116  * wait is the amount of time used between retransmitting a call if
 117  * no response has been heard; retransmission occurs until the actual
 118  * rpc call times out.
 119  *
 120  * sendsz and recvsz are the maximum allowable packet sizes that can be
 121  * sent and received.
 122  */
 123 CLIENT *
 124 clntudp_bufcreate (struct sockaddr_in *raddr, u_long program, u_long version,
 125                    struct timeval wait, int *sockp, u_int sendsz,
 126                    u_int recvsz)
 127 {
 128   CLIENT *cl;
 129   struct cu_data *cu = NULL;
 130   struct rpc_msg call_msg;
 131
 132   cl = (CLIENT *) mem_alloc (sizeof (CLIENT));
 133   sendsz = ((sendsz + 3) / 4) * 4;
 134   recvsz = ((recvsz + 3) / 4) * 4;
 135   cu = (struct cu_data *) mem_alloc (sizeof (*cu) + sendsz + recvsz);
 136   if (cl == NULL || cu == NULL)
 137     {
 138       struct rpc_createerr *ce = &get_rpc_createerr ();
 139 #ifdef USE_IN_LIBIO
 140       if (_IO_fwide (stderr, 0) > 0)
 141         (void) __fwprintf (stderr, L"%s",
 142                            _("clntudp_create: out of memory\n"));
 143       else
 144 #endif
 145         (void) fputs (_("clntudp_create: out of memory\n"), stderr);
 146       ce->cf_stat = RPC_SYSTEMERROR;
 147       ce->cf_error.re_errno = ENOMEM;
 148       goto fooy;
 149     }
 150   cu->cu_outbuf = &cu->cu_inbuf[recvsz];
 151
 152   if (raddr->sin_port == 0)
 153     {
 154       u_short port;
 155       if ((port =
 156            pmap_getport (raddr, program, version, IPPROTO_UDP)) == 0)
 157         {
 158           goto fooy;
 159         }
 160       raddr->sin_port = htons (port);
 161     }
 162   cl->cl_ops = &udp_ops;
 163   cl->cl_private = (caddr_t) cu;
 164   cu->cu_raddr = *raddr;
 165   cu->cu_rlen = sizeof (cu->cu_raddr);
 166   cu->cu_wait = wait;
 167   cu->cu_total.tv_sec = -1;
 168   cu->cu_total.tv_usec = -1;
 169   cu->cu_sendsz = sendsz;
 170   cu->cu_recvsz = recvsz;
 171   call_msg.rm_xid = _create_xid ();
 172   call_msg.rm_direction = CALL;
 173   call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
 174   call_msg.rm_call.cb_prog = program;
 175   call_msg.rm_call.cb_vers = version;
 176   INTUSE(xdrmem_create) (&(cu->cu_outxdrs), cu->cu_outbuf, sendsz, XDR_ENCODE);
 177   if (!INTUSE(xdr_callhdr) (&(cu->cu_outxdrs), &call_msg))
 178     {
 179       goto fooy;
 180     }
 181   cu->cu_xdrpos = XDR_GETPOS (&(cu->cu_outxdrs));
 182   if (*sockp < 0)
 183     {
 184       int dontblock = 1;
 185
 186       *sockp = __socket (AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 187       if (*sockp < 0)
 188         {
 189           struct rpc_createerr *ce = &get_rpc_createerr ();
 190           ce->cf_stat = RPC_SYSTEMERROR;
 191           ce->cf_error.re_errno = errno;
 192           goto fooy;
 193         }
 194       /* attempt to bind to prov port */
 195       (void) bindresvport (*sockp, (struct sockaddr_in *) 0);
 196       /* the sockets rpc controls are non-blocking */
 197       (void) __ioctl (*sockp, FIONBIO, (char *) &dontblock);
 198 #ifdef IP_RECVERR
 199       {
 200         int on = 1;
 201         __setsockopt (*sockp, SOL_IP, IP_RECVERR, &on, sizeof(on));
 202       }
 203 #endif
 204       cu->cu_closeit = TRUE;
 205     }
 206   else
 207     {
 208       cu->cu_closeit = FALSE;
 209     }
 210   cu->cu_sock = *sockp;
 211   cl->cl_auth = INTUSE(authnone_create) ();
 212   return cl;
 213 fooy:
 214   if (cu)
 215     mem_free ((caddr_t) cu, sizeof (*cu) + sendsz + recvsz);
 216   if (cl)
 217     mem_free ((caddr_t) cl, sizeof (CLIENT));
 218   return (CLIENT *) NULL;
 219 }
 220 INTDEF (clntudp_bufcreate)
 221
 222 CLIENT *
 223 clntudp_create (raddr, program, version, wait, sockp)
 224      struct sockaddr_in *raddr;
 225      u_long program;
 226      u_long version;
 227      struct timeval wait;
 228      int *sockp;
 229 {
 230   return INTUSE(clntudp_bufcreate) (raddr, program, version, wait, sockp,
 231                                     UDPMSGSIZE, UDPMSGSIZE);
 232 }
 233 INTDEF (clntudp_create)
 234
 235 static int
 236 is_network_up (int sock)
 237 {
 238   struct ifaddrs *ifa;
 239
 240   if (getifaddrs (&ifa) != 0)
 241     return 0;
 242
 243   struct ifaddrs *run = ifa;
 244   while (run != NULL)
 245     {
 246       if ((run->ifa_flags & IFF_UP) != 0
 247           && run->ifa_addr->sa_family == AF_INET)
 248         break;
 249
 250       run = run->ifa_next;
 251     }
 252
 253   freeifaddrs (ifa);
 254
 255   return run != NULL;
 256 }
 257
 258 static enum clnt_stat
 259 clntudp_call (cl, proc, xargs, argsp, xresults, resultsp, utimeout)
 260      CLIENT *cl;        /* client handle */
 261      u_long proc;               /* procedure number */
 262      xdrproc_t xargs;           /* xdr routine for args */
 263      caddr_t argsp;             /* pointer to args */
 264      xdrproc_t xresults;        /* xdr routine for results */
 265      caddr_t resultsp;          /* pointer to results */
 266      struct timeval utimeout;   /* seconds to wait before giving up */
 267 {
 268   struct cu_data *cu = (struct cu_data *) cl->cl_private;
 269   XDR *xdrs;
 270   int outlen = 0;
 271   int inlen;
 272   socklen_t fromlen;
 273   struct pollfd fd;
 274   int milliseconds = (cu->cu_wait.tv_sec * 1000) +
 275     (cu->cu_wait.tv_usec / 1000);
 276   struct sockaddr_in from;
 277   struct rpc_msg reply_msg;
 278   XDR reply_xdrs;
 279   struct timeval time_waited;
 280   bool_t ok;
 281   int nrefreshes = 2;           /* number of times to refresh cred */
 282   struct timeval timeout;
 283   int anyup;                    /* any network interface up */
 284
 285   if (cu->cu_total.tv_usec == -1)
 286     {
 287       timeout = utimeout;       /* use supplied timeout */
 288     }
 289   else
 290     {
 291       timeout = cu->cu_total;   /* use default timeout */
 292     }
 293
 294   time_waited.tv_sec = 0;
 295   time_waited.tv_usec = 0;
 296 call_again:
 297   xdrs = &(cu->cu_outxdrs);
 298   if (xargs == NULL)
 299     goto get_reply;
 300   xdrs->x_op = XDR_ENCODE;
 301   XDR_SETPOS (xdrs, cu->cu_xdrpos);
 302   /*
 303    * the transaction is the first thing in the out buffer
 304    */
 305   (*(uint32_t *) (cu->cu_outbuf))++;
 306   if ((!XDR_PUTLONG (xdrs, (long *) &proc)) ||
 307       (!AUTH_MARSHALL (cl->cl_auth, xdrs)) ||
 308       (!(*xargs) (xdrs, argsp)))
 309     return (cu->cu_error.re_status = RPC_CANTENCODEARGS);
 310   outlen = (int) XDR_GETPOS (xdrs);
 311
 312 send_again:
 313   if (__sendto (cu->cu_sock, cu->cu_outbuf, outlen, 0,
 314                 (struct sockaddr *) &(cu->cu_raddr), cu->cu_rlen)
 315       != outlen)
 316     {
 317       cu->cu_error.re_errno = errno;
 318       return (cu->cu_error.re_status = RPC_CANTSEND);
 319     }
 320
 321   /*
 322    * Hack to provide rpc-based message passing
 323    */
 324   if (timeout.tv_sec == 0 && timeout.tv_usec == 0)
 325     {
 326       return (cu->cu_error.re_status = RPC_TIMEDOUT);
 327     }
 328  get_reply:
 329   /*
 330    * sub-optimal code appears here because we have
 331    * some clock time to spare while the packets are in flight.
 332    * (We assume that this is actually only executed once.)
 333    */
 334   reply_msg.acpted_rply.ar_verf = _null_auth;
 335   reply_msg.acpted_rply.ar_results.where = resultsp;
 336   reply_msg.acpted_rply.ar_results.proc = xresults;
 337   fd.fd = cu->cu_sock;
 338   fd.events = POLLIN;
 339   anyup = 0;
 340   for (;;)
 341     {
 342       switch (__poll (&fd, 1, milliseconds))
 343         {
 344
 345         case 0:
 346           if (anyup == 0)
 347             {
 348               anyup = is_network_up (cu->cu_sock);
 349               if (!anyup)
 350                 return (cu->cu_error.re_status = RPC_CANTRECV);
 351             }
 352
 353           time_waited.tv_sec += cu->cu_wait.tv_sec;
 354           time_waited.tv_usec += cu->cu_wait.tv_usec;
 355           while (time_waited.tv_usec >= 1000000)
 356             {
 357               time_waited.tv_sec++;
 358               time_waited.tv_usec -= 1000000;
 359             }
 360           if ((time_waited.tv_sec < timeout.tv_sec) ||
 361               ((time_waited.tv_sec == timeout.tv_sec) &&
 362                (time_waited.tv_usec < timeout.tv_usec)))
 363             goto send_again;
 364           return (cu->cu_error.re_status = RPC_TIMEDOUT);
 365
 366           /*
 367            * buggy in other cases because time_waited is not being
 368            * updated.
 369            */
 370         case -1:
 371           if (errno == EINTR)
 372             continue;
 373           cu->cu_error.re_errno = errno;
 374           return (cu->cu_error.re_status = RPC_CANTRECV);
 375         }
 376 #ifdef IP_RECVERR
 377       if (fd.revents & POLLERR)
 378         {
 379           struct msghdr msg;
 380           struct cmsghdr *cmsg;
 381           struct sock_extended_err *e;
 382           struct sockaddr_in err_addr;
 383           struct iovec iov;
 384           char *cbuf = (char *) alloca (outlen + 256);
 385           int ret;
 386
 387           iov.iov_base = cbuf + 256;
 388           iov.iov_len = outlen;
 389           msg.msg_name = (void *) &err_addr;
 390           msg.msg_namelen = sizeof (err_addr);
 391           msg.msg_iov = &iov;
 392           msg.msg_iovlen = 1;
 393           msg.msg_flags = 0;
 394           msg.msg_control = cbuf;
 395           msg.msg_controllen = 256;
 396           ret = __recvmsg (cu->cu_sock, &msg, MSG_ERRQUEUE);
 397           if (ret >= 0
 398               && memcmp (cbuf + 256, cu->cu_outbuf, ret) == 0
 399               && (msg.msg_flags & MSG_ERRQUEUE)
 400               && ((msg.msg_namelen == 0
 401                    && ret >= 12)
 402                   || (msg.msg_namelen == sizeof (err_addr)
 403                       && err_addr.sin_family == AF_INET
 404                       && memcmp (&err_addr.sin_addr, &cu->cu_raddr.sin_addr,
 405                                  sizeof (err_addr.sin_addr)) == 0
 406                       && err_addr.sin_port == cu->cu_raddr.sin_port)))
 407             for (cmsg = CMSG_FIRSTHDR (&msg); cmsg;
 408                  cmsg = CMSG_NXTHDR (&msg, cmsg))
 409               if (cmsg->cmsg_level == SOL_IP && cmsg->cmsg_type == IP_RECVERR)
 410                 {
 411                   e = (struct sock_extended_err *) CMSG_DATA(cmsg);
 412                   cu->cu_error.re_errno = e->ee_errno;
 413                   return (cu->cu_error.re_status = RPC_CANTRECV);
 414                 }
 415         }
 416 #endif
 417       do
 418         {
 419           fromlen = sizeof (struct sockaddr);
 420           inlen = __recvfrom (cu->cu_sock, cu->cu_inbuf,
 421                               (int) cu->cu_recvsz, 0,
 422                               (struct sockaddr *) &from, &fromlen);
 423         }
 424       while (inlen < 0 && errno == EINTR);
 425       if (inlen < 0)
 426         {
 427           if (errno == EWOULDBLOCK)
 428             continue;
 429           cu->cu_error.re_errno = errno;
 430           return (cu->cu_error.re_status = RPC_CANTRECV);
 431         }
 432       if (inlen < 4)
 433         continue;
 434
 435       /* see if reply transaction id matches sent id.
 436         Don't do this if we only wait for a replay */
 437       if (xargs != NULL
 438           && (*((u_int32_t *) (cu->cu_inbuf))
 439               != *((u_int32_t *) (cu->cu_outbuf))))
 440         continue;
 441       /* we now assume we have the proper reply */
 442       break;
 443     }
 444
 445   /*
 446    * now decode and validate the response
 447    */
 448   INTUSE(xdrmem_create) (&reply_xdrs, cu->cu_inbuf, (u_int) inlen, XDR_DECODE);
 449   ok = INTUSE(xdr_replymsg) (&reply_xdrs, &reply_msg);
 450   /* XDR_DESTROY(&reply_xdrs);  save a few cycles on noop destroy */
 451   if (ok)
 452     {
 453       _seterr_reply (&reply_msg, &(cu->cu_error));
 454       if (cu->cu_error.re_status == RPC_SUCCESS)
 455         {
 456           if (!AUTH_VALIDATE (cl->cl_auth,
 457                               &reply_msg.acpted_rply.ar_verf))
 458             {
 459               cu->cu_error.re_status = RPC_AUTHERROR;
 460               cu->cu_error.re_why = AUTH_INVALIDRESP;
 461             }
 462           if (reply_msg.acpted_rply.ar_verf.oa_base != NULL)
 463             {
 464               xdrs->x_op = XDR_FREE;
 465               (void) INTUSE(xdr_opaque_auth) (xdrs,
 466                                               &(reply_msg.acpted_rply.ar_verf));
 467             }
 468         }                       /* end successful completion */
 469       else
 470         {
 471           /* maybe our credentials need to be refreshed ... */
 472           if (nrefreshes > 0 && AUTH_REFRESH (cl->cl_auth))
 473             {
 474               nrefreshes--;
 475               goto call_again;
 476             }
 477         }                       /* end of unsuccessful completion */
 478     }                           /* end of valid reply message */
 479   else
 480     {
 481       cu->cu_error.re_status = RPC_CANTDECODERES;
 482     }
 483   return cu->cu_error.re_status;
 484 }
 485
 486 static void
 487 clntudp_geterr (CLIENT *cl, struct rpc_err *errp)
 488 {
 489   struct cu_data *cu = (struct cu_data *) cl->cl_private;
 490
 491   *errp = cu->cu_error;
 492 }
 493
 494
 495 static bool_t
 496 clntudp_freeres (CLIENT *cl, xdrproc_t xdr_res, caddr_t res_ptr)
 497 {
 498   struct cu_data *cu = (struct cu_data *) cl->cl_private;
 499   XDR *xdrs = &(cu->cu_outxdrs);
 500
 501   xdrs->x_op = XDR_FREE;
 502   return (*xdr_res) (xdrs, res_ptr);
 503 }
 504
 505 static void
 506 clntudp_abort (void)
 507 {
 508 }
 509
 510 static bool_t
 511 clntudp_control (CLIENT *cl, int request, char *info)
 512 {
 513   struct cu_data *cu = (struct cu_data *) cl->cl_private;
 514
 515   switch (request)
 516     {
 517     case CLSET_FD_CLOSE:
 518       cu->cu_closeit = TRUE;
 519       break;
 520     case CLSET_FD_NCLOSE:
 521       cu->cu_closeit = FALSE;
 522       break;
 523     case CLSET_TIMEOUT:
 524       cu->cu_total = *(struct timeval *) info;
 525       break;
 526     case CLGET_TIMEOUT:
 527       *(struct timeval *) info = cu->cu_total;
 528       break;
 529     case CLSET_RETRY_TIMEOUT:
 530       cu->cu_wait = *(struct timeval *) info;
 531       break;
 532     case CLGET_RETRY_TIMEOUT:
 533       *(struct timeval *) info = cu->cu_wait;
 534       break;
 535     case CLGET_SERVER_ADDR:
 536       *(struct sockaddr_in *) info = cu->cu_raddr;
 537       break;
 538     case CLGET_FD:
 539       *(int *)info = cu->cu_sock;
 540       break;
 541     case CLGET_XID:
 542       /*
 543        * use the knowledge that xid is the
 544        * first element in the call structure *.
 545        * This will get the xid of the PREVIOUS call
 546        */
 547       *(u_long *)info = ntohl(*(u_long *)cu->cu_outbuf);
 548       break;
 549     case CLSET_XID:
 550       /* This will set the xid of the NEXT call */
 551       *(u_long *)cu->cu_outbuf =  htonl(*(u_long *)info - 1);
 552       /* decrement by 1 as clntudp_call() increments once */
 553     case CLGET_VERS:
 554       /*
 555        * This RELIES on the information that, in the call body,
 556        * the version number field is the fifth field from the
 557        * begining of the RPC header. MUST be changed if the
 558        * call_struct is changed
 559        */
 560       *(u_long *)info = ntohl(*(u_long *)(cu->cu_outbuf +
 561                                           4 * BYTES_PER_XDR_UNIT));
 562       break;
 563     case CLSET_VERS:
 564       *(u_long *)(cu->cu_outbuf + 4 * BYTES_PER_XDR_UNIT)
 565         = htonl(*(u_long *)info);
 566       break;
 567     case CLGET_PROG:
 568       /*
 569        * This RELIES on the information that, in the call body,
 570        * the program number field is the  field from the
 571        * begining of the RPC header. MUST be changed if the
 572        * call_struct is changed
 573        */
 574       *(u_long *)info = ntohl(*(u_long *)(cu->cu_outbuf +
 575                                           3 * BYTES_PER_XDR_UNIT));
 576       break;
 577     case CLSET_PROG:
 578       *(u_long *)(cu->cu_outbuf + 3 * BYTES_PER_XDR_UNIT)
 579         = htonl(*(u_long *)info);
 580       break;
 581     /* The following are only possible with TI-RPC */
 582     case CLGET_SVC_ADDR:
 583     case CLSET_SVC_ADDR:
 584     case CLSET_PUSH_TIMOD:
 585     case CLSET_POP_TIMOD:
 586     default:
 587       return FALSE;
 588     }
 589   return TRUE;
 590 }
 591
 592 static void
 593 clntudp_destroy (CLIENT *cl)
 594 {
 595   struct cu_data *cu = (struct cu_data *) cl->cl_private;
 596
 597   if (cu->cu_closeit)
 598     {
 599       (void) __close (cu->cu_sock);
 600     }
 601   XDR_DESTROY (&(cu->cu_outxdrs));
 602   mem_free ((caddr_t) cu, (sizeof (*cu) + cu->cu_sendsz + cu->cu_recvsz));
 603   mem_free ((caddr_t) cl, sizeof (CLIENT));
 604 }